Methods of multiple SS block transmissions and RRM measurement in a wideband carrier

ABSTRACT

Aspects of the disclosure provide a method for radio resource management (RRM) measurement. The method can include receiving, by processing circuitry of a user equipment (UE), an RRM measurement configuration from a base station (BS) in a beamformed communication system. The RRM measurement configuration indicates presence of multiple quasi collocated (QCLed) frequency domain multiplexed (FDMed) reference signal (RS) transmissions in a carrier. The method can further includes perform RRM measurement according to the received RRM measurement configuration using one or more of the multiple QCLed FDMed RS transmissions.

INCORPORATION BY REFERENCE

This present disclosure claims the benefit of International ApplicationNo. PCT/CN2017/097148, “Methods of Multiple SS Block Transmissions andRRM Measurement in a Wideband Carrier” filed on Aug. 11, 2017, which isincorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to wireless communications, andspecifically relates to radio resource management (RRM) measurement in awireless system.

BACKGROUND

The background description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent the work is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of filing, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure.

New Radio (NR) air interface of 5th generation (5G) wirelesscommunication systems supports much wider channel bandwidth (CBW) (e.g.,400 MHz) compared to that of Long-Term Evolution standards (e.g., 20MHz). The wide CBW enables more efficient use of resources than existingcarrier aggregation (CA) mechanisms.

In a wireless communication system, radio resource management (RRM)measurement provides measurement results to support a wide range ofoperations including channel dependent scheduling, power control, idleand connected mode mobility, and the like. For example, RRM measurementsdefined in some communication standards can include reference signalreceived power (RSRP), reference signal received quality (RSRQ), andreceived signal strength indicator (RSSI).

SUMMARY

Aspects of the disclosure provide a method for radio resource management(RRM) measurement. The method can include receiving, by processingcircuitry of a user equipment (UE), an RRM measurement configurationfrom a base station (BS) in a beamformed communication system. The RRMmeasurement configuration indicates presence of multiple quasicollocated (QCLed) frequency domain multiplexed (FDMed) reference signal(RS) transmissions in a carrier. The method can further includes performRRM measurement according to the received RRM measurement configurationusing any one or more of the multiple QCLed FDMed RS transmissions.

In an embodiment, RSs of the multiple QCLed FDMed RS transmissionsinclude synchronization signals (SSs) of SS blocks, channel stateinformation reference signals (CSI-RSs), or a combination of SSs of SSblocks and CSI-RSs.

An embodiment of the method further includes performing reference signalreceived power (RSRP) measurement using more than one of the multipleQCLed FDMed RS transmissions, wherein received power on resourceelements (REs) corresponding to the more than one of the QCLed FDMed RStransmissions is averaged to obtain an RSRP measurement.

An embodiment of the method further includes operating on a bandwidthpart (BWP) including a subset of the multiple QCLed FDMed RStransmissions, and performing RSRP measurement using one or more of thesubset of the multiple QCLed FDMed RS transmissions.

An embodiment of the method further includes operating on a BWP of thecarrier without the multiple QCLed FDMed RS transmissions, and switchingto a BWP including a subset of the multiple QCLed FDMed RS transmissionsto perform inter-frequency RSRP measurement using the subset of themultiple QCLed FDMed RS transmissions.

An embodiment of the method further includes operating on a BWP of thecarrier containing a subset of the multiple QCLed FDMed RStransmissions, performing RSRP measurement on the BWP using the subsetof the multiple QCLed FDMed RS transmissions to obtain an RSRPmeasurement result, performing received signal strength indicator (RSSI)measurement on a measurement bandwidth indicated by the RRM measurementconfiguration that is different from the BWP to obtain an RSSImeasurement result, and calculating a reference signal received quality(RSRQ) using the RSRP measurement result and the RSSI measurementresult. In one example, the measurement bandwidth indicated by the RRMmeasurement configuration for the RSSI measurement overlaps or does notoverlap the BWP.

An embodiment of the method further includes operating on a BWP of thecarrier without the multiple QCLed FDMed RS transmissions, performinginter-frequency RSRP measurement on a first measurement bandwidth usinga subset of the multiple QCLed FDMed RS transmissions to obtain an RSRPmeasurement, performing inter-frequency RSSI measurement on a secondmeasurement bandwidth that is different from the first measurementbandwidth to obtain an RSSI measurement, and calculating an RSRQmeasurement based on the RSRP measurement and the RSSI measurement.

An embodiment of the method further includes performing inter-frequencyRSRP measurement on a first measurement bandwidth using a subset of themultiple QCLed FDMed RS transmissions to obtain an RSRP measurementbased on a first measurement gap configuration indicated by the RRMmeasurement configuration, performing inter-frequency RSSI measurementon a second measurement bandwidth that is different from the firstmeasurement bandwidth to obtain an RSSI measurement based on a secondmeasurement gap configuration indicated by the RRM measurementconfiguration that is independent from the first measurement gapconfiguration, and calculating an RSRQ measurement based on the RSRPmeasurement and the RSSI measurement.

An embodiment of the method further includes performing RSRP measurementon a first measurement bandwidth using a subset of the multiple QCLedFDMed RS transmissions to obtain an RSRP measurement, performing RSSImeasurement on a second measurement bandwidth that is different from thefirst measurement bandwidth, and on time domain measurement resourcesindicated by the RRM measurement configuration to obtain an RSSImeasurement, wherein the time domain measurement resources includesorthogonal frequency division multiplexing (OFDM) symbols that carry ordoes not carry RSs of the multiple QCLed FDMed RS transmissions, andcalculating an RSRQ measurement based on the RSRP measurement and theRSSI measurement.

An embodiment of the method further includes operating on a first BWP ofthe carrier, performing a radio frequency (RF) tuning during a firstmeasurement gap to cover a second BWP overlapping the first BWP and ameasurement bandwidth, performing RRM measurement on the measurementbandwidth while performing data reception on the first BWP, andperforming an RF tuning during a second measurement gap to switch backto the first BWP. In one example, the RRM measurement on the measurementbandwidth includes RSRP and/or RSSI measurement.

Aspects of the disclosure provide a second method for RRM measurement.The second method can include transmitting, by processing circuitry of abase station, an RRM measurement configuration to a UE in a beamformedcommunication system. The RRM measurement configuration indicatespresence of multiple quasi collocated (QCLed) frequency domainmultiplexed (FDMed) reference signal (RS) transmissions in a carrier.The second method further includes receiving measurement resultsobtained according to the RRM measurement configuration from the UE.

In one example, RSs of the multiple QCLed FDMed RS transmissions includesynchronization signals (SSs) of SS blocks, channel state informationreference signals (CSI-RSs), or a combination of SSs of SS blocks andCSI-RSs.

In one example, the RRM measurement configuration indicates frequencylocations and periods of the multiple QCLed FDMed RS transmissions.

In one example, the second method includes transmitting a bandwidth part(BWP) configuration to the UE indicating an active BWP including atleast one of the multiple QCLed FDMed RS transmissions, and transmittingthe RRM measurement configuration indicating a measurement bandwidth forreceived signal strength indicator (RSSI) measurement that is differentfrom the active BWP configured to the UE.

In one example, the second method includes transmitting a BWPconfiguration to the UE indicating an active BWP without the multipleQCLed FDMed RS transmissions, and transmitting the RRM measurementconfiguration indicating a first measurement bandwidth and a firstmeasurement gap configuration for reference signal received power (RSRP)measurement on the first measurement bandwidth that includes a subset ofthe multiple QCLed FDMed RS transmissions, and a second measurementbandwidth and second measurement gap configuration for RSSI measurementon the second measurement bandwidth. The second measurement bandwidth isdifferent from the first measurement bandwidth, and the secondmeasurement configuration is independent from the first measurementconfiguration.

In one example, the second method further includes transmitting the RRMmeasurement configuration that indicates a first measurement bandwidthfor RSRP measurement including a subset of the multiple QCLed FDMed RStransmissions, a second measurement bandwidth for RSRQ measurement thatis different from the first measurement bandwidth, and time domainresources for the RSSI measurement including a set of OFDM symbols thatcarries or does not carry RSs of the multiple QCLed FDMed RStransmissions.

In one example, the second method further includes transmitting a BWPconfiguration indicating an active BWP to the UE, transmitting the RRMmeasurement configuration indicating a measurement gap configurationspecifying a first measurement gap and a second measurement gap at abeginning and an end, respectively, of a measurement occasion, and arepetition period of the measurement occasion, and transmitting dataduring an interval between the first and second measurement gaps on theactive BWP.

Aspects of the disclosure further provide a UE. The UE can includeprocessing circuitry configured to receive a radio resource management(RRM) measurement configuration from a base station (BS) in a beamformedcommunication system. The RRM measurement configuration indicatespresence of multiple quasi collocated (QCLed) frequency domainmultiplexed (FDMed) reference signal (RS) transmissions in a carrier.The processing circuitry can further be configured to perform RRMmeasurement according to the received RRM measurement configurationusing any one or more of the multiple QCLed FDMed RS transmissions.

BRIEF DESCRIPTION OF DRAWINGS

Various embodiments of this disclosure that are proposed as exampleswill be described in detail with reference to the following figures,wherein like numerals reference like elements, and wherein:

FIG. 1 shows a beam-based wireless communication system according to anembodiment of the disclosure;

FIG. 2 shows an example of a synchronization signal (SS) block accordingto an embodiment of the disclosure;

FIG. 3 shows an example SS block transmission configuration according toan embodiment of the disclosure;

FIG. 4 shows example frame structures corresponding to differentsubcarrier spacings according to an embodiment of the disclosure;

FIG. 5 shows a table including example SS block configurations accordingto an embodiment of the disclosure;

FIGS. 6-8 illustrate SS block configurations of cases A-E in FIG. 5;

FIG. 9 shows an example configuration of multiple SS block transmissionsin a wideband carrier according to embodiments of the disclosure;

FIG. 10 shows a frequency domain measurement resource configurationexample of received signal strength indicator (RSSI) measurement in awideband carrier according to an embodiment of the disclosure;

FIG. 11 shows a further frequency domain measurement resourcesconfiguration example of RSSI measurement in a wideband carrieraccording to an embodiment of the disclosure;

FIG. 12 shows a time domain measurement resource configuration exampleof RSSI measurement in a wideband carrier;

FIG. 13 shows a measurement gap configuration example of inter-frequencyradio resource management (RRM) measurement according to an embodimentof the disclosure;

FIG. 14 shows a measurement gap configuration example forinter-frequency RRM measurement according to an embodiment of thedisclosure;

FIG. 15 shows an example RRM measurement process according to anembodiment of the disclosure; and

FIG. 16 shows an exemplary apparatus according to embodiments of thedisclosure.

DETAILED DESCRIPTION

FIG. 1 shows a beam-based wireless communication system 100 according toan embodiment of the disclosure. The system 100 can include a userequipment (UE) 110, a first base station (BS) 120, and a second BS 130.The system 100 can employ the 5th generation (5G) technologies developedby the 3rd Generation Partnership Project (3GPP). For example,millimeter Wave (mm-Wave) frequency bands and beamforming technologiescan be employed in the system 100. Accordingly, the UE 110, the BSs120-130 can perform beamformed transmission or reception. In beamformedtransmission, wireless signal energy can be focused on a specificdirection to cover a target serving region. As a result, an increasedantenna transmission (Tx) gain can be achieved in contrast toomnidirectional antenna transmission. Similarly, in beamformedreception, wireless signal energy received from a specific direction canbe combined to obtain a higher antenna reception (Rx) gain in contrastto omnidirectional antenna reception. The increased Tx or Rx gain cancompensate path loss or penetration loss in mm-Wave signal transmission.

The BS 120 or 130 can be a base station implementing a gNB node asspecified in 5G New Radio (NR) air interface standards developed by3GPP. The BS 120 or 130 can be configured to control one or more antennaarrays to form directional Tx or Rx beams for transmitting or receivingwireless signals. In some examples, different sets of antenna arrays aredistributed at different locations to cover different serving areas.Each such set of antenna arrays can be referred to as a transmissionreception point (TRP).

In FIG. 1 example, the BS 120 can control a TRP to form Tx beams 121-126to cover a cell 128. The beams 121-126 can be generated towardsdifferent directions. The beams 121-126 can be generated simultaneouslyor in different time intervals in different examples. In one example,the BS 120 is configured to perform a beam sweeping 127 to transmitL1/L2 control channel and/or data channel signals. During the beamsweeping 127, Tx beams 121-126 towards different directions can besuccessively formed in a time division multiplex (TDM) manner to coverthe cell 128. During each time interval for transmission of one of thebeams 121-126, a set of L1/L2 control channel data and/or data channeldata can be transmitted. The beam sweeping 127 can be performedrepeatedly with a certain periodicity. In alternative examples, thebeams 121-126 may be generated in a way other than performing a beamsweeping. For example, multiple beams towards different directions maybe generated at a same time. In other examples, different from FIG. 1examples where the beams 121-126 are generated horizontally, the BS 120can generate beams towards different horizontal or vertical directions.In an example, the maximum number of beams generated from a TRP can be64.

Each beam 121-126 can be associated with various reference signals (RSs)129, such as channel-state information reference signal (CSI-RS),demodulation reference signal (DMRS), or synchronization signals (SSs)(e.g., primary synchronization signal (PSS), and secondarysynchronization signal (SSS)). Those RSs can serve for differentpurposes depending on related configurations and different scenarios.For example, some RSs can be used for radio resource management (RRM)measurement. Each beam 121-126, when transmitted at different occasions,may carry different signals, such as different L1/L2 data or controlchannels, or different RSs.

The BS 130 can operate in a way similar to the BS 120. For example, theBS 130 can control a TRP to transmit Tx beams 131-136 to cover a cell138. The BS 130 may transmit the beams 131-136 in a beam sweepingmanner, or may form a subset of the beams 131-136 simultaneously atdifferent time instances. Similarly, each of the beams 131-136 may carryvarious RSs 139.

The UE 110 can be a mobile phone, a laptop computer, a vehicle carriedmobile communication device, a utility meter, and the like. Similarly,the UE 110 can employ one or more antenna arrays to generate directionalTx or Rx beams for transmitting or receiving wireless signals. In FIG. 1example, the UE 110 is within the coverage of the cells 128 and 138,however, is connected to the BS 120 and served by the cell 128.Accordingly, the cell 128 is referred to as a serving cell of the UE 110while the cell 138 is referred to as a neighbor cell of the UE 110.While only one UE 110 is shown in FIG. 1, a plurality of UEs can bedistributed within the cells 128 and/or 138, and served by the BS 120 or130, or other BSs not shown in FIG. 1.

In one example, the beams 121-126 of the cell 128 can be identifiedusing synchronization signal blocks (SS blocks) (also referred to asSS/PBCH blocks). For example, an SS block can include SSs (e.g., PSS,SSS) and a physical broadcast channel (PBCH) carried on severalconsecutive symbols in an orthogonal frequency division multiplexing(OFDM) based system. For example, the BS 120 may periodically perform abeam sweeping to transmit a sequence of SS blocks with each beamcorresponding to each SS block. The sequence of SS blocks may each carryan SS block index indicating a timing or location of each SS block amongthe sequence of SS blocks. Thus, each of the beams 121-126 can beassociated with (or corresponding to) such an SS block index.

In one example, the UE 110 performs radio resource management (RRM)measurement and report measurement results to its serving cell 128. Themeasurement results are useful to support a wide range of operationsincluding channel dependent scheduling, power control, idle andconnected mode mobility, beam management, beam tracking, bandwidth partswitching, and the like. For example, RRM measurements as defined in3GPP standards can include reference signal received power (RSRP),reference signal received quality (RSRQ), and received signal strengthindicator (RSSI), signal-to-noise and interference ratio (SINR).

For example, RSRP can be measured by the UE 110 over cell-specific RSs(e.g., SS or CSI-RS) within a measurement bandwidth over a measurementperiod. RSRP reflects a signal strength of received signals, and isuseful for indicative of a cell coverage. RSRP can be defined as alinear average over power contributions of resource elements (REs) thatcarry the cell-specific RSs with a measurement bandwidth over ameasurement period.

For example, RSRQ is a ratio of RSRP to RSSI corresponding to a specificdownlink carrier. For example, RSRQ is defined as a ratio ofNxRSRP/carrier RSSI, where N is a number of resource blocks in a carrierRSSI measurement bandwidth. RSSI is total power from all sources,including serving and non-serving cells, adjacent channel interference,and thermal noise, observed in certain OFDM symbols of measurement timeresources in a measurement bandwidth (including the N resource blocks),linearly averaged over the respective OFDM symbols.

In different scenarios, RRM measurement can be performed with differentreference signals, such as SSs and/or DMRS carried in SS blocks, CSI-RSsconfigured for RRM measurement, and the like. In some examples, SS basedRRM measurement can be performed when the UE 110 is in radio resourcecontrol (RRC) connected mode, RRC inactive mode, or RRC idle mode.CSI-RS based RRM measurement can be performed when the UE 110 is in RRCconnected mode.

In one example, RSRP and/or RSRQ measurement results are used for cellreselection when the UE 110 is in RRC idle mode, and handover when theUE 110 is in RRC connected mode. For example, when in RRC connectedstate, the UE 110 may report the RRM measurement results to the servingcell 128. When in RRC idle state, the UE 110 does not report the RRMmeasurement results, and may use the RRM measurement resultsautonomously for cell reselection.

In some examples, the UE 110 may have a plurality of neighbor cells,such as 2, 3 or 10 neighbor cells. Accordingly, the UE 110 may performRRM measurement on multiple neighbor cells in addition to the servingcell 128. For example, a list of to-be-measured neighbor cells can beconfigured by the BS 120 to the UE 110. Or, the UE 110 can measureneighbor cells detected by the UE 110.

In addition, the UE 110 may perform RRM measurement in anintra-frequency manner or an inter-frequency manner. For example, whenperforming intra-frequency measurement, the UE 110 measures RSs receivedwithin a bandwidth of a carrier the serving cell 128 operates on. TheRSs can be transmitted from either the serving cell 128 or neighborcells. When performing inter-frequency measurement, the UE 110 leavesthe carrier the serving cell 128 operates on, and switches to adifferent carrier to receive RSs transmitted either from the servingcell 128 or neighbor cells. For the purpose of inter-frequencymeasurement, a measurement gap may be configured. In one example, intime domain, physical layer measurement periods for RSRP measurement aredefined as 200 ms and 480 ms for intra-frequency and inter-frequencyRSRP, respectively.

In one example, RSRP is performed for indicating signal qualities atbeam level, and a cell level signal quality can be derived based on beamlevel measurement results. For example, RSRP corresponding to each ofthe beams 121-126 can be measured at the UE 110 based on the RSs (e.g.,SS or CSI-RS) associated with each beam. For example, the resulting beamlevel RSRP can be associated with a beam index and used for beamtracking or beam management purpose. In order to evaluate a signalquality of a cell, for example, for a handover operation, a subset ofthe beam level RSRP measurement results can be employed. In one example,a number of beam level RSRPs having a value above a threshold, or anumber of the beam level RSRPs with highest values, can be averaged toderive a cell level RSRP to reflect a quality of a cell.

In one example, the BS 120 configures the UE 110 to perform RRMmeasurement and report respective measurement results in accordance witha measurement configuration. The measurement configuration is providedby means of dedicated signaling (e.g., RRC messages) or broadcastingsignaling. For example, the measurement configuration may include agroup of parameters, such as measurement objects, reportingconfigurations, measurement identities, quantity configurations,measurement gaps, and the like. For example, the measurement objectsparameters may specify a list of objects on which the UE 110 shallperform the measurements. For example, for intra-frequency andinter-frequency measurements, a measurement object indicatesfrequency/time location and subcarrier spacing of RSs to be measured.Associated with this measurement object, a list of cells and a list ofcell specific offsets may be specified. The UE 110 measures and reportson the serving cell(s), listed cells, and/or detected cells.

FIG. 2 shows an example of an SS block 200 used in the system 100according to an embodiment of the disclosure. The SS block 200 caninclude a PSS 201, an SSS 202, and a PBCH 203 (represented with shadedareas designated with numbers of 201, 202, and 203). Those signals canbe carried in REs on a time-frequency resource grid as shown in FIG. 2.In addition, the SS block 200 can carry DMRSs (not shown) in a subset ofREs in the shaded area 203. The REs carrying DMRSs are not used forcarrying PBCH signals in one example.

In one example, the SS block 200 can be distributed over 4 OFDM symbolsin time domain and occupy a 20 resource block (RB) bandwidth infrequency domain. As shown in FIG. 2, the 4 OFDM symbols are numberedfrom 0 to 4, while the 20 RB bandwidth includes 240 subcarriers numberedfrom 0 to 239. Specifically, the PSS 201 can occupy REs at symbol 0 andsubcarriers 56-182. The SSS 202 can occupy REs at symbol 2 andsubcarriers 56-182. The PBCH 203 can be located at symbols 1-3 occupying20 RBs at symbols 1 and 3, and 8 RBs (96 subcarriers) at symbol 2.

In one example, the SS block 200 is configured to carry bits of an SSblock index by using the DMRSs and the PBCH 203. In one example, bydecoding the PSS 201 and the SSS 202, a physical layer cellidentification (ID) can be determined. The cell ID indicates which cellthe SS block 200 is associated with.

In some examples, RSRP is measured using SS blocks. Such measurementsare referred to as SS-RSRP. For example, SS-RSRP is defined as a linearaverage over power contributions of REs that carry SSSs. In someexamples, the DMRS for the PBCH 203 and CSI-RS in addition to the SSSsmay be used for RSRP measurement. In some examples, a beam level RSRP ismeasured using RSs (e.g., SSS, DMRS, CSI-RS) corresponding to SS blockswith a same SS block index, and a same physical layer cell ID. The SSblocks can be periodically transmitted during a measurement time window.

FIG. 3 shows an example SS block transmission configuration 300according to an embodiment of the disclosure. According to theconfiguration 300, a sequence 301 of SS blocks, referred to as SS blockburst set 301, can be transmitted with a periodicity 320 (e.g., 20 ms)in a sequence of radio frames. The SS block set 301 can be confinedwithin a half frame transmission window 310 (e.g., 5 ms). Eachconfigured SS block can have an SS block index (e.g., from #1 to #n).The SS blocks of the SS block set 301 are configured as candidate SSblocks, but may not be used for actual transmissions of SS blocks.

For example, a cell 340 employs 6 beams from #1 to #6 to cover a servingarea and transmits SS blocks based on the configuration 300.Accordingly, only a subset 330 of the SS block set 301 is transmitted.For example, the transmitted SS blocks 330 may include the first sixcandidate SS blocks of the SS block set 301 each corresponding to one ofthe beams #1-#6. Resources corresponding to other candidate SS blocksfrom #7 to #n can be used for transmission of data other than SS blocks.

FIG. 4 shows example frame structures used in the system 100corresponding to different subcarrier spacings according to anembodiment of the disclosure. A radio frame 410 can last for 10 ms andinclude 10 subframes that each last for 1 ms. Corresponding to differentnumerologies and respective subcarrier spacings, a subframe may includedifferent number of slots. For example, for a subcarrier spacing of 15kHz, 30 kHz, 60 kHz, 120 kHz, or 240 kHz, a respective subframe 420-460can include 1, 2, 4, 8, or 16 slots, respectively. Each slot may include14 OFDM symbols in one example.

FIG. 5 shows a table 500 including example SS block configurationswithin a 5 ms half frame time window according to an embodiment of thedisclosure. The table 500 shows five cases A-E of SS blockconfigurations in five rows of the table 500. The five cases A-Ecorrespond to different subcarrier spacing configurations of a cell. Foreach case, indexes of first symbols in each SS block within a half frame(e.g., 5 ms) are specified.

For example, in case A with 15 kHz subcarrier spacing, the first symbolsof the candidate SS blocks have symbol indexes of {2, 8}+14n. Forcarrier frequencies smaller than or equal to 3 GHz, n=0, 1,corresponding to a total number of L=4 SS blocks. Accordingly, the 4candidate SS blocks can have SS block indexes in an ascending order intime from 0 to 4. For carrier frequencies larger than 3 GHz and smallerthan or equal to 6 GHz, n=0, 1, 2, 3, corresponding to a total number ofL=8 candidate SS blocks. Accordingly, the 8 candidate SS blocks can haveSS block indexes in an ascending order in time from 0 to 8.

For another example, in case D with 120 kHz subcarrier spacing, thefirst symbols of the candidate SS blocks have symbol indexes of {4, 8,16, 20}+28n. For carrier frequencies larger than 6 GHz, n=0, 1, 2, 3, 5,6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18, corresponding to a total numberof L=64 candidate SS blocks. Accordingly, the 64 candidate SS blocks canhave SS block indexes in an ascending order in time from 0 to 64.

FIGS. 6-8 illustrate the SS block configurations of cases A-E in FIG. 5.Specifically, FIG. 6 shows six SS block configurations 601-606corresponding to different combinations of subcarrier spacings andfrequency bands. In each configuration 601-606, slots containing SSblocks within a half frame window are shown with shaded rectangles 610.FIGS. 7 and 8 show zoomed-in views of how SS blocks 701 or 801 aredistributed over sequences of symbols in time domain.

FIG. 9 shows an example configuration 900 of multiple SS blocktransmissions in a wideband carrier according to embodiments of thedisclosure. In one example, the BS 120 is configured to operate on awideband carrier 901 having a much wider channel bandwidth (e.g., up to400 MHz, or more than 400 MHz) compared with a Long Term Evolution (LTE)system that typically has a maximum component carrier (CC) bandwidth of20 MHz. Compared with carrier aggregation (CA) scheme in an LTE system,operating on a wider channel bandwidth has advantages of more efficientand flexible resource scheduling, lower control overhead, and higherspeed of activating or deactivating a portion of the wideband carrier(e.g., bandwidth part switching).

In addition, the BS 120 is configured to support intra-band CA tosupport coexistence of UEs having different RF capabilities. Forexample, a wideband UE is capable of covering the whole bandwidth of thewideband carrier 901 with one radio frequency (RF) chain, andaccordingly can be configured with the entirety of the wideband carrier901. A narrowband UE having a single RF chain can cover a portion of thewideband carrier 901, and can be configured with an intra-band CC. A CAUE that has multiple RF chains and is capable of intra-band CA can beconfigured with a set of intra-band CC with CA.

Further, the BS 120 is configured to support bandwidth part (BWP)operations to achieve power savings. According to the disclosure, a BWPcan be defined as a group of contiguous physical resource blocks (PRBs).A bandwidth of the BWP can be at least as large as one SS blockbandwidth, but the BWP may or may not contain SS blocks. Multiple BWPsmay be configured to a UE, for example, by RRC signaling. The multipleBWPs may overlap with each other. The UE may operate on an active BWPwhich is one of the multiple BWPs at a given time, and switch to anotherBWP when needed. For example, the UE can access to a default BWPduringan initial access process, and switch to one of the multiple configuredBWPsafter RRC connection establishment. For example, a wideband UE canoperate in a narrowband mode with a low data rate on a BWP having anarrower bandwidth than the wideband carrier 901, and switch to a widerBWP to facilitate a higher data rate.

As shown, multiple frequency domain multiplexed (FDMed) SS blocks910-930 are transmitted within the wideband carrier 901. The multipleFDMed SS blocks 910-930 can be distributed at different frequencylocations 941-943. Providing multiple FDMed SS blocks may have multipleadvantages. For example, there can be more flexibility for configuringUEs to operate on BWPs at different frequency locations where an SSblocks are available for various operations. In scenarios where a UEsearches for an SS block during an initial access process, multipleavailable SS blocks can expedite the initial access process. For a CA UEhaving multiple RF chains, multiple SS blocks at different frequencylocations provide means for synchronizations at different intra-band CCfor each of the multiple RF chains.

The multiple FDMed SS blocks 910-930 can belong to different SS blockburst sets 911-931 that are each transmitted periodically. Accordingly,each of the multiple FDMed SS blocks 910-930 can be transmittedperiodically forming multiple transmissions 912, 922, and 932 of FDMedSS blocks. For example, each transmission 912, 922, or 932 maycorrespond to a sequence of SS blocks 910, 920, or 930.

The SS block burst sets 911-931 may have different SS block transmissionconfigurations. For example, each of the SS block burst sets 911-913 mayhave different periodicity. For example, a bandwidth part 902 includingthe SS block burst set 911 is used as a default bandwidth part forinitial access. Accordingly, the SS block burst set 911 including the SSblock 910 may be configured with a shorter period than other SS blockburst sets 921-931 such that a beam sweeping operation may be performedmore rapidly during the initial access. Accordingly, each of themultiple FDMed SS blocks 910-930 may be transmitted periodically withdifferent periodicities. Different from what is shown in FIG. 9 wherethe SS blocks 910-930 are present at a same time instance, latertransmitted FDMed SS blocks 910-930 at different frequency locations941-943 may not by synchronized.

In one example, the multiple FDMed SS blocks 910-930 are configured tobe equivalent for RRM measurement. For example, the SS blocks 910-930can be transmitted from a same antenna port with a same beam, and a samepower level. In addition, channel characteristics are consistent atdifferent frequency locations within the wideband carrier 901. Undersuch configuration and channel condition, SS block based or SS based RRMmeasurement (e.g., RSRP) performed at one frequency location using arespective SS block can reflect the channel condition of the wholewideband carrier 901. Accordingly, the SS block based RRM measurementcan be performed with any one of the multiple FDMed SS blocks 910-930,and corresponding RRM measurement results would be equivalentirrespective which one of the multiple FDMed SS blocks 910-930 is used.The multiple FDMed SS blocks 910-930 configured to be equivalent for RRMmeasurement are said to be quasi collocated (QCLed) for RRM measurement.

Under the configuration of QCLed multiple FDMed SS blocks 910-930, RRMmeasurement (e.g., RSRP) can be performed in different ways depending onUE RF capability, wideband or narrowband operating mode, and active BWPconfiguration.

In a first example, a first UE 951, which is a narrowband UE or awideband UE operating in narrowband mode, operates on the BWP 902. TheUE 951 can perform RSRP measurement using the transmission 912 of the SSblocks 910. For example, five measurements may be repeatedly performedusing five SS blocks 910 during a measurement interval to obtain fiveRSRP values that are subsequently averaged resulting in an averaged RSRPvalue. The five SS blocks 910 may carry a same cell ID. The averagedRSRP value can correspond to a beam on which the sequence of five SSblocks 910 are transmitted. The beam belongs to a cell identified by thecell ID carried in the respective SS blocks 910. In addition, theaverage RSRP value can reflect channel conditions at, for example,frequency locations 942-943. Inter-frequency RRM measurement withconfiguration of measurement gaps and BWP switching can be avoided.

In a second example, a wideband UE 952 operates covering the wholewideband carrier 901. In a first case, the wideband UE 952 uses any oneof the transmissions 912-932 of the multiple SS blocks 910-930, andperforms RRM measurement using the selected sequence of SS blocks in away similar to the first example. In a second case, the wideband UE 952uses multiple QCLed sequences of FDMed SS blocks, such as thetransmissions 941 and 942, 942 and 943, 941 and 943, or thetransmissions 941-943, and performs RRM measurement using the selectedsequences of FDMed SS blocks. The multiple transmissions 941-943 maycarry the same cell ID in the SS blocks 910-930 such that the respectiveSS blocks 910-930 can be distinguished from other SS blocks of neighborcells. In addition, the SS blocks 910-930 of the multiple transmissions912-932 may carry a same beam index corresponding to the beam used forthe transmissions 912-932.

In the second case, as shown in FIG. 9, within a same measurement timeperiod 961, there can be more REs carrying SSs distributed at multiplefrequency locations 941-943 than using one transmission 912 of FDMed SSblocks 910. As a result, times and duration of the RRM measurement canbe reduced while maintaining a same level of measurement accuracy. Forexample, compared with performing five times of measurement in the firstexample, three times of measurement in time domain may be performedassuming the multiple FDMed SS block transmissions are synchronized. Dueto a decrease of the measurement times, power consumption of the UE 952can be reduced.

In the above first and second cases, selection of one or more SS blocktransmissions for the RRM measurement can be determined by the UE 952,or can be configured by the BS 120 in different examples.

In a third example, a narrowband UE 953 operates on a BWP 903. The BWP903 is not configured with a transmission of SS blocks. Accordingly, theUE 953 may use any one of the multiple FDMed SS block transmissions912-932 to perform inter-frequency RRM measurement (e.g., RSRP).Measurement gaps can accordingly be configured and used.

In a fourth example, a wideband UE 954 operates on the BWP 903. The UE934 may use one or multiple of the FDMed SS block transmissions 912-932to perform inter-frequency RRM measurement. Measurement gaps canaccordingly be configured and used.

To facilitate RRM measurement with the QCLed multiple FDMed SS blocktransmissions 912-932 within the wideband carrier 901, the BS 120transmitting on the wideband carrier 901 may inform the UEs 951-954 thepresence and parameters of the QCLed multiple FDMed SS blocktransmissions 912-932. For example, a configuration of FDMed SS blocktransmissions 921-932 may be signaled to the UEs 951-954 using dedicatedRRC messages or broadcasting system information, or may be transmittedto the UEs 951-954 as a part of an RRM measurement configuration. Theconfiguration may specify frequency locations and time domain locations(e.g., an offset with respect to an initial system frame number) of eachFDMed SS block transmission 921-932. The configuration may furtherspecify transmission configurations of each SS block burst set 911-931,such as transmission periods, actually transmitted SS blocks amongcandidate SS block positions, to-be-measured beam indexes if needed. Theconfiguration may indicate that the respective FDMed SS blocktransmissions are QCLed or equivalent for RRM measurement.

In one example, anchor SS blocks are defined and utilized for RRMmeasurement. For example, an anchor SS block can be configured at afrequency location in each of a serving cell and neighbor cells. Inother words, those anchor SS blocks can be transmitted by the servingcell and neighbor cells in a given frequency layer so that a UE canperform cell search to find potential cells identified by the anchor SSblocks and perform intra-frequency RRM measurement. For an initialaccess, some default anchor SS blocks in a default BWP can be assumed bythe UE for cell access. For a UE in RRC connected mode or idle mode, aset of anchor SS blocks can be indicated by system information ordedicated RRC signaling for RRM measurement. Multiple sets of anchor SSblocks at multiple frequency locations may be configured in a widebandcarrier, such that UEs may be distributed among those multiple frequencylocations for load balancing when in RRC idle mode or RRC connectedmode.

Accordingly, in FIG. 9 example, the QCLed multiple FDMed SS blocktransmissions 912-932 may be anchor SS blocks. In alternative examples,the ACLed multiple FDMed SS block transmissions 912-932 may includeanchor SS blocks as well as non-anchor SS blocks (e.g., SS blocksconfigured in a serving cell but no corresponding SS blocks configuredin neighbor cells at the same frequency location).

FIG. 10 shows a frequency domain measurement resource configurationexample of RSSI measurement in a wideband carrier 1030 according to anembodiment of the disclosure. For example, multiple QCLed FDMed SS blocktransmissions 1041-1044 are configured on the wideband carrier 1030. AUE 1051, which may be a narrowband UE or a wideband UE operating innarrowband mode, operates on an active BWP 1010. According to an RRMmeasurement configuration, the UE 1051 may perform RSRP measurementusing the SS block transmission 1041. For example, multiple RSRPmeasurements may be obtained and averaged to obtain an RSRP value. Theresulting RSRP value can be used to represent RSRP values at anyfrequency locations within the wideband carrier 1030 due to the QCLed SSblock transmissions.

According to the RRM measurement configuration, the UE 1051 may performRSSI measurement at a measurement bandwidth specified by the RRMmeasurement configuration. For example, a frequency location and a sizeof the measurement bandwidth may be specified to indicate frequencydomain measurement resources. Time domain measurement resources can alsobe specified. The specified measurement bandwidths can be the same as ordifferent from a measurement bandwidth (e.g., bandwidth 1011 of the SSblock transmission 1041) for the above RSRP measurement, includingoverlapping the measurement bandwidth 1011 for the above RSRPmeasurement.

In a first example, the UE 1051 may be configured to perform RSRQmeasurement on a BWP 1020 for supporting a BWP switching operation. Forexample, the UE 1051 may accordingly perform RSSI measurement to obtainan RSSI value corresponding to the BWP 1020. Multiple measurements maybe performed at different time locations on OFDM symbols specified bythe respective RRM measurement configuration. An averaged RSSI value cansubsequently be obtained. Then, the UE 1051 may calculate an RSRQ basedon the averaged RSSI value obtained on the measurement BWP 1020, and theRSRP value obtained on the measurement BWP 1010. To facilitate the RSSImeasurement at the BWP 1020, measurement gaps may be configuredcorresponding to the frequency and time domain measurement resourcesspecified by the RRM measurement configuration.

In a second example, the UE 1051 may be configured to perform RSRQmeasurement on the whole wideband carrier 1030 for supporting a cellreselection or handover operation. Similarly, an RSSI valuecorresponding to the whole wideband carrier 1030 may be obtained basedon the RRM measurement configuration. An RSRQ value may be calculatedbased on the RSSI value obtained on the wideband carrier 1030 and theRSRP value obtained on the BWP 1010.

In alternative examples, the RRM measurement configuration may notspecify a measurement bandwidth for RSRQ/QSSI measurement. Accordingly,the RSSI measurement may be performed on a default measurementbandwidth, such as the BWP 1010 or the bandwidth 1011 occupied by SSblocks of the SS block transmission 1041.

FIG. 11 shows a further frequency domain measurement resourcesconfiguration example of RSSI measurement in a wideband carrier 1130according to an embodiment of the disclosure. Similar to FIG. 10, QCLedFDMed multiple SS block transmissions 1141-1143 are configured in awideband carrier 1130. However, a UE 1151 operates in a BWP 1110 withoutSS block transmissions. Based on an RRM measurement configurationreceived from a serving BS, the UE 1151 may be configured to perform anRSRP measurement using any one of the SS block transmissions 1141-1143.For example, the RSRP measurement is performed using the SS blocktransmission 1141, and on a measurement bandwidth 1111 corresponding tothe SS block transmission 1141.

According to the respective RRM measurement configuration, the UE 1151may perform RSSI measurement at a configured measurement bandwidth, suchas a BWP 1120 and/or the entirety of the wideband carrier 1130. Theconfigured RSSI measurement bandwidth is different from the RSRPmeasurement bandwidth 1111.

In addition, for both the RSRP and RSSI measurement, RSRP measurementgaps and RSSI measurement gaps are independently configured. Forexample, respective frequency and time domain resources for the RSRP andRSSI measurement can be different with each other. Accordingly, the RSRPand RSSI measurement gaps may have different parameters. Or, in otherwords, the RSRP and RSSI measurement gaps are independent from eachother. The parameters of a measurement gap configuration may include gapoffset, gap duration, gap repetition period, and the like.

FIG. 12 shows a time domain measurement resource configuration exampleof RSSI measurement in a wideband carrier 1203. A sequence of slots 1210indexed from 0 to 11 are shown in FIG. 12. Each slot may include anumber of OFDM symbols (e.g., 14 OFDM symbols per slot). The first 10slots indexed from 0 to 9 are within a 5 ms half frame 1220 thatcontains an SS block burst set 1230 in the first 4 slots. For example,each of the first 4 slots may include two SS blocks. Each SS block ofthe SS block burst set 1230 may be associated or transmitted from a Txbeam. The SS block burst set 1230 may be configured and indicated by arespective serving cell of a UE 1251 as QCLed with other SS block burstsets (not shown) within the wideband carrier. For example, SS blocks indifferent SS block burst set corresponding to a same Tx beam can beconfigured to be QCLed.

The UE 1251 operates on an active BWP 1201 that includes the SS blockburst set 1230. According to an RRM configuration received from theserving cell, the UE 1251 may perform RSRP measurement using the QCLedSS block burst set 1230. For example, a set of RSRP values may beobtained for each SS block of the SS block burst set 1230 or eachrespective beam. The RSRP measurement may be repeatedly performed with asequence of SS block burst sets including the SS block burst set 1230.An averaged RSRP value can be obtained for each respective Tx beam.

The UE 1251 may perform RSSI measurement according to the RRMmeasurement configuration. The RRM measurement configuration may specifyfrequency domain measurement resources, such as a BWP 1202. The RRMmeasurement configuration may also specify time domain measurementresources.

In a first example, the time domain measurement resources are configuredto be a first set of OFDM symbols 1241 overlapping the SS block burstset 1230. As shown in FIGS. 7-8, a subset of OFDM symbols of a slotcontaining an SS block are occupied by SS block symbols, while theremaining OFDM symbols of the same slot are not occupied by SS blocksymbols. Accordingly, the first set of OFDM symbols 1241 may or may notoverlap the respective SS block symbols in different RRM configurations.In addition, the first set of OFDM symbols 1241 may or may not becontiguous in time domain.

In a second example, the time domain measurement resources areconfigured to be a second set of OFDM symbols 1242 that are outside ofthe SS block burst set 1230 but within the respective half frame 1220.In a third example, the time domain measurement resources are configuredto be a third set of OFDM symbols 1243 that are outside the respectivehalf frame 1220.

In some examples, the time domain measurement resources for RSSImeasurement are configured in a way that the set of OFDM symbols 1241,1242, or 1243 correspond to a specific Tx beam. For example, the set ofOFDM symbols 1241, 1242, or 1243 are transmitted from a specific beam.In this way, an RSSI value can be measured for the respective beam.Similarly, the time domain measurement resources for RSSi measurementmay be configured for multiple beams, such that an RSSI value may bemeasured for each of the multiple beams. Further, those RSSI values ofmultiple beams may be averaged to obtain a cell level RSSI value.

While only one configured set of OFDM symbols 1241, 1242, or 1243 isshown in FIG. 12, the configured set of OFDM symbols 1241, 1242, or 1243can repeat periodically. As a result, multiple times of RSSI measurementmay be performed with respective repeatedly transmitted OFDM symbols.

Based on the RSRP measurement results obtained on the active BWP 1201and the RSSI measurement results obtained on the BWP 1202, RSRQmeasurement results can accordingly be calculated. Similarly, the aboveRSSI or RSSQ measurement can be performed on the entirety of thewideband carrier 1203 according to an RRM measurement configuration.

FIG. 13 shows a measurement gap configuration example of inter-frequencyRRM measurement according to an embodiment of the disclosure. A UE 1351,which can be a narrowband UE or a wideband UE operating in narrowbandmode, operates on an active BWP 1301, and performs inter-frequency RRMmeasurement (e.g., RSRP or RSSI) on a BWP 1302 according to an RRMmeasurement configuration. The RRM measurement configuration may includea measurement gap configuration specifying measurement gap parameters.The measurement gap configuration may specify a gap length (or gapduration) 1310, a gap repetition period 1320, and a gap offset (notshown) indicating a starting location of the measurement gaps.

During the RRM measurement process, the UE 1351 may receive data atintervals 1331, 1332, or 1333, however, cannot conduct data reception atmeasurement gaps 1310 or 1340. During the measurement gap 1310, at afirst time period 1311, the UE 1351 performs RF tuning and switches tothe BWP 1302. At a second time period 1312, the UE 1351 performs RRMmeasurement on the BWP 1302 without conducting data reception. At athird time period 1313, the UE 1351 tunes back to the active BWP 1301. Asimilar operation as in the measurement gap 1310 can be repeated at themeasurement gap 1340.

FIG. 14 shows a measurement gap configuration example forinter-frequency RRM measurement according to an embodiment of thedisclosure. A UE 1451 operates on an active BWP 1401, and is configuredto perform inter-frequency RRM measurement (e.g., RSRP or RSSI) on a BWP1402 according to an RRM measurement configuration. Instead of switchingfrom the active BWP 1401 to the target BWP 1402 as conducted in FIG. 13example, the UE 1451 may switch to a BWP 1403 that includes both the BWP1401 and the BWP 1402. For example, the UE 1451 is capable of covering ameasurement bandwidth including the two BWPs 1401 and 1402.

As an example, two similar measurement occasions 1410-1420 are shown inFIG. 14. In the first measurement occasion 1410, a first measurement gap1411 is configured during which the UE 1451 performs RF tuning andswitches to the BWP 1403. A measurement and reception interval 1412follows the first measurement gap 1411 during which the UE 1451 performsRRM measurement and data reception simultaneously. A second measurementgap 1413 follows the measurement and reception interval 1412 duringwhich the UE 1451 switches back to the BWP 1401. As shown, a totalduration of measurement gaps 1411 and 1413 can be shorter than themeasurement gap 1310 in FIG. 13. As a result, disturbing to datareception caused by inter-frequency RRM measurement is reduced.

Corresponding to the inter-frequency RRM measurement scheme shown inFIG. 14, the respective RRM measurement configuration can accordinglyconfigure duration of each measurement occasion 1410 or 1420, ameasurement occasion repetition period 1430, a first and secondmeasurement gap 1411 and 1413 at a beginning and an end of eachmeasurement occasion.

In some embodiments, CSI-RSs are used in place of SSs in SS blocksserving functions of synchronization or RRM measurement. Accordingly,the SS block based RSRP measurement processes or mechanisms in variousexamples described herein are also applicable to scenarios where CSI-RSsare used in place of SSs in SS blocks. For example, multiple sets ofCSI-RSs can be configured to be associated with a Tx beam, andtransmitted in multiple frequency locations in a wideband carrier. ThoseCSI-RSs can be configured to be QCLed or equivalent for RRM measurement.Thus, those QCLed FDMed multiple CSI-RS transmissions can be used forRRM measurement in a way similar to the QCLed FDMed multiple SS blocktransmissions. For example, RRM measurement results measured using oneset of the CSI-RSs at a frequency location can be used to reflectchannel conditions at other frequency locations within the widebandcarrier. Similarly, anchor CSI-RS sets can be configured at a servingcell and neighbor cells to serve the functions of anchor SS blocks. TheCSI-RSs can be used independently from SS blocks in a wideband carrier,or can be used in combination with SS blocks in a wideband carrier.

FIG. 15 shows an example RRM measurement process 1500 according to anembodiment of the disclosure. During the process, a UE 1501 receives anRRM configuration from a BS 1502, and conducts RRM measurementaccordingly on a wideband carrier, for example, having a bandwidth up to400 MHz, or wider than 400 MHz.

At S1510, an initial access process is performed between the UE 1501 andthe BS 1502. As a result, an RRC connection is established between theUE 1501 and the BS 1502. For example, the UE 1501 may perform theinitial access process on a default BWP, or searches for a BWP thatincludes transmission of SS blocks.

At S1520, UE capability information is transmitted from the UE 1501 tothe BS 1502. In various examples, the UE 1501 may have differentcapabilities in terms of maximum operating bandwidth, numerologies, CAcapability, and the like.

At S1530, the BS 1502 transmits a BWP configuration to the UE 1501. TheBWP configuration can be created according to the capability of the UE1501. For example, a BWP having a suitable bandwidth, frequencylocation, numerology, and the like, is configured to the UE 1501. Theconfigured BWP may be different from the BWP on which the UE 1501performs the initial access process. For a wideband UE, the configuredBWP can be the entirety or a portion of the wideband carrier. Inaddition, the BWP configuration may be created according to otheradditional factors, such as load balancing among different BWPs,subscription information associated with the UE 1501. In response toreception of the BWP configuration, the UE 1501 may switch to the BWPspecified by the BWP configuration.

At S1540, an RRM measurement configuration is transmitted from the BS1502 to the UE 1501. In one example, the measurement configuration iscarried in a radio resource control (RRC) message. In one example, themeasurement configuration is included in system information block (SIB)that is broadcasted from the BS 120.

In one example, the RRM measurement configuration indicates presence andparameters of multiple QCLed FDMed RS transmissions in the widebandcarrier. The multiple QCLed FDMed RSs can be SSs of SS blocks orCSI-RSs. The RRM measurement configuration may indicate presence andparameters of multiple QCLed FDMed RS transmissions in the widebandcarrier for multiple cells including a serving cell and some neighborcells.

The RRM measurement configuration also indicates parameters for RRMmeasurement in the multiple cells. For example, the RRM measurementconfiguration indicates the RRM measurement results include RSRP, and/orRSSI/RSSQ measurements. For a wideband UE 1501, the RRM measurementconfiguration may indicate which one or more of the multiple QCLed FDMedRS transmissions are used for the RSRP measurement per each of themultiple cells. In alternative examples, the UE 1501 determines whichone or more of the multiple QCLed FDMed RS transmissions are used forthe RSRP measurement in different cells. For a narrow band UE 1501operating on the configured BWP that does not contain SS blocks orCRI-RSs, the RRM measurement configuration may include a measurement gapconfiguration for inter-frequency RSRQ measurement in the serving cellor one of the neighbor cells.

For the RSSI/RSRQ measurement, the RRM measurement configuration mayindicate a measurement bandwidth including frequency domain measurementresources. The indicated measurement bandwidth can be different from theconfigured BWP which the UE 1501 operates on. In addition, the RRMmeasurement configuration may indicate a measurement gap configurationfor the RSSI/RSRQ measurement that can be different from the measurementgap configuration for the RSRP measurement.

Further for the RSSI/RSRQ measurement, the RRM measurement configurationmay indicate time domain measurement resources (e.g., a set of OFDMsymbols).

The measurement gap configurations specified by the RRM measurementconfiguration, either for RSRP measurement or RSSI measurement, can bebased on one of the two inter-frequency schemes illustrated in FIGS. 13and 14.

In various examples, the RRM measurement configuration may additionallyinclude other information suitable for conducting the RRM measurement.For example, the measurement configuration may include the followingparameters: measurement objects, reporting configurations, measurementidentities, quantity configurations, measurement gaps, and the like.

For example, the measurement objects may provide a list of objects(cells) on which the UE shall perform the measurement. A measurementobject can be associated with a carrier frequency. The reportingconfigurations may provide a list of reporting configurations. One ormore reporting configurations may be specified for each cell. Areporting configuration may specify a reporting criterion that triggersthe UE 1501 to send a measurement report. The triggers can either beperiodical or a single event description. A reporting configuration mayfurther specify a reporting format. For example, the format can includequantities per cell and per beam that the UE 1501 includes in themeasurement report (e.g., RSRP/RSRQ/SINR) and other associatedinformation such as a maximum number of cells and/or beams per cell toreport.

At S1550, RSs for RRM measurement are transmitted from the BS 1502 tothe UE 1501. For example, corresponding to the RRM measurementconfiguration transmitted at S1540, the QCLed FDMed RSs are transmitted.The S1550 may take place before or after the S1540. However, inalternative examples, the transmissions of the QCLed FDMed RSs on thewideband carrier in the serving cell or the neighbor cells may alreadytake place before the UE 1501 accesses to the BS 1502 at S1510.

At S1560, the UE 1501 performs RRM measurement according to the RRMmeasurement configuration using the QCLed FDMed RS transmissions in theserving cell and the neighbor cells. For example, RSRP measurementresults may be obtained using the RSs of the serving cell or neighborcells by intra- or inter-frequency measurement. The respective RSRPmeasurement process in one cell may use one of the multiple QCLed FDMedRS transmissions with a longer measurement period, or, in contrast, morethan one of the multiple QCLed FDMed RS transmissions with a shortermeasurement period.

RSSI measurement results obtained at one or more measurement frequencylocations can be used in combination with RSRP measurement resultsobtained at locations different from the RSSI measurement using RSs ofdifferent serving cell or neighbor cells to calculate cell specific RSRQmeasurement results.

At S1570, the RRM measurement results (e.g., RSRP or RSRQ) can bereported from the UE 1501 to the BS 1502. For example, the reportedmeasurement results may be carried in an RRC message. For example, whena reporting criterion is met, a measurement report can be triggered. Theprocess 1500 may terminates thereafter.

FIG. 16 shows an exemplary apparatus 1600 according to embodiments ofthe disclosure. The apparatus 1600 can be configured to perform variousfunctions in accordance with one or more embodiments or examplesdescribed herein. Thus, the apparatus 1600 can provide means forimplementation of techniques, processes, functions, components, systemsdescribed herein. For example, the apparatus 1600 can be used toimplement functions of the UEs 110 and 1501 or the BS 120, 130 and 1502in various embodiments and examples described herein. The apparatus 1600can be a general purpose computer in some embodiments, and can be adevice including specially designed circuits to implement variousfunctions, components, or processes described herein in otherembodiments. The apparatus 1600 can include processing circuitry 1610, amemory 1620, and a radio frequency (RF) module 1630.

In various examples, the processing circuitry 1610 can include circuitryconfigured to perform the functions and processes described herein incombination with software or without software. In various examples, theprocessing circuitry can be a digital signal processor (DSP), anapplication specific integrated circuit (ASIC), programmable logicdevices (PLDs), field programmable gate arrays (FPGAs), digitallyenhanced circuits, or comparable device or a combination thereof.

In some other examples, the processing circuitry 1610 can be a centralprocessing unit (CPU) configured to execute program instructions toperform various functions and processes described herein. Accordingly,the memory 1620 can be configured to store program instructions. Theprocessing circuitry 1610, when executing the program instructions, canperform the functions and processes. The memory 1620 can further storeother programs or data, such as operating systems, application programs,and the like. The memory 1620 can include a read only memory (ROM), arandom access memory (RAM), a flash memory, a solid state memory, a harddisk drive, an optical disk drive, and the like.

The RF module 1630 receives processed data signal from the processingcircuitry 1610 and transmits the signal in a beam-formed wirelesscommunication network via an antenna 1640, or vice versa. The RF module1630 can include a digital to analog convertor (DAC), an analog todigital converter (ADC), a frequency up convertor, a frequency downconverter, filters, and amplifiers for reception and transmissionoperations. The RF module 1640 can include multi-antenna circuitry(e.g., analog signal phase/amplitude control units) for beamformingoperations. The antenna 1640 can include one or more antenna arrays.

The apparatus 1600 can optionally include other components, such asinput and output devices, additional or signal processing circuitry, andthe like. Accordingly, the apparatus 1600 may be capable of performingother additional functions, such as executing application programs, andprocessing alternative communication protocols.

While aspects of the present disclosure have been described inconjunction with the specific embodiments thereof that are proposed asexamples, alternatives, modifications, and variations to the examplesmay be made. Accordingly, embodiments as set forth herein are intendedto be illustrative and not limiting. There are changes that may be madewithout departing from the scope of the claims set forth below.

The invention claimed is:
 1. A method, comprising: receiving, byprocessing circuitry of a user equipment (UE), a radio resourcemanagement (RRM) measurement configuration from a base station (BS) in abeamformed communication system, the RRM measurement configurationindicating presence of multiple quasi collocated (QCLed) frequencydomain multiplexed (FDMed) reference signal (RS) transmissions in acarrier, the multiple QCLed FDMed RS transmissions including a firstsequence of RS transmissions at a first frequency location and a secondsequence of RS transmissions at a second frequency location, first RSsof the first sequence of RS transmissions and second RSs of the secondsequence of RS transmission being equivalent in terms of RRMmeasurement; and performing RRM measurement according to the receivedRRM measurement configuration using one or more of the multiple QCLedFDMed RS transmissions.
 2. The method of claim 1, wherein the first andsecond RSs of the multiple QCLed FDMed RS transmissions includesynchronization signals (SSs) of SS blocks, channel state informationreference signals (CSI-RSs), or a combination of SSs of SS blocks andCSI-RSs.
 3. The method of claim 1, further comprising: performingreference signal received power (RSRP) measurement using more than oneof the multiple QCLed FDMed RS transmissions, wherein received power onresource elements (REs) corresponding to the more than one of the QCLedFDMed RS transmissions is averaged to obtain an RSRP measurement.
 4. Themethod of claim 1, further comprising: operating on a bandwidth part(BWP) including a subset of the multiple QCLed FDMed RS transmissions;and performing RSRP measurement using one or more of the subset of themultiple QCLed FDMed RS transmissions.
 5. The method of claim 1, furthercomprising: operating on a BWP of the carrier without the multiple QCLedFDMed RS transmissions; and switching to a BWP including a subset of themultiple QCLed FDMed RS transmissions to perform inter-frequency RSRPmeasurement using the subset of the multiple QCLed FDMed RStransmissions.
 6. The method of claim 1, further comprising: operatingon a BWP of the carrier containing a subset of the multiple QCLed FDMedRS transmissions; performing RSRP measurement on the BWP using thesubset of the multiple QCLed FDMed RS transmissions to obtain an RSRPmeasurement result; performing received signal strength indicator (RSSI)measurement on a measurement bandwidth and/or a frequency locationindicated by the RRM measurement configuration that is different fromthe BWP to obtain an RSSI measurement result; and calculating areference signal received quality (RSRQ) using the RSRP measurementresult and the RSSI measurement result.
 7. The method of claim 6,wherein the measurement bandwidth indicated by the RRM measurementconfiguration for the RSSI measurement overlaps or does not overlap theBWP.
 8. The method of claim 1, further comprising: operating on a BWP ofthe carrier without the multiple QCLed FDMed RS transmissions;performing inter-frequency RSRP measurement on a first measurementbandwidth using a subset of the multiple QCLed FDMed RS transmissions toobtain an RSRP measurement; performing inter-frequency RSSI measurementon a second measurement bandwidth that is different from the firstmeasurement bandwidth to obtain an RSSI measurement; and calculating anRSRQ measurement based on the RSRP measurement and the RSSI measurement.9. The method of claim 1, further comprising: performing inter-frequencyRSRP measurement on a first measurement bandwidth using a subset of themultiple QCLed FDMed RS transmissions to obtain an RSRP measurementbased on a first measurement gap configuration indicated by the RRMmeasurement configuration; performing inter-frequency RSSI measurementon a second measurement bandwidth that is different from the firstmeasurement bandwidth to obtain an RSSI measurement based on a secondmeasurement gap configuration indicated by the RRM measurementconfiguration that is independent from the first measurement gapconfiguration; and calculating an RSRQ measurement based on the RSRPmeasurement and the RSSI measurement.
 10. The method of claim 1, furthercomprising: performing RSRP measurement on a first measurement bandwidthusing a subset of the multiple QCLed FDMed RS transmissions to obtain anRSRP measurement; performing RSSI measurement on a second measurementbandwidth that is different from the first measurement bandwidth, and ontime domain measurement resources indicated by the RRM measurementconfiguration to obtain an RSSI measurement, wherein the time domainmeasurement resources includes orthogonal frequency divisionmultiplexing (OFDM) symbols that carry or does not carry RSs of themultiple QCLed FDMed RS transmissions; calculating an RSRQ measurementbased on the RSRP measurement and the RSSI measurement.
 11. The methodof claim 1, further comprising: operating on a first BWP of the carrier;performing a radio frequency (RF) tuning during a first measurement gapto cover a second BWP overlapping the first BWP and a measurementbandwidth; performing RRM measurement on the measurement bandwidth whileperforming data reception on the first BWP; and performing an RF tuningduring a second measurement gap to switch back to the first BWP.
 12. Themethod of claim 11, wherein the RRM measurement on the measurementbandwidth includes RSRP and/or RSSI measurement.
 13. A method,comprising: transmitting, by processing circuitry of a base station, aradio resource management (RRM) measurement configuration to a userequipment (UE) in a beamformed communication system, the RRM measurementconfiguration indicating presence of multiple quasi collocated (QCLed)frequency domain multiplexed (FDMed) reference signal (RS) transmissionsin a carrier transmitted from the base station, the multiple QCLed FDMedRS transmissions including a first sequence of RS transmissions at afirst frequency location and a second sequence of RS transmissions at asecond frequency location, first RSs of the first sequence of RStransmissions and second RSs of the second sequence of RS transmissionbeing equivalent in terms of RRM measurement; and receiving measurementresults obtained according to the RRM measurement configuration from theUE.
 14. The method of claim 13, wherein the first and second RSs of themultiple QCLed FDMed RS transmissions include synchronization signals(SSs) of SS blocks, channel state information reference signals(CSI-RSs), or a combination of SSs of SS blocks and CSI-RSs.
 15. Themethod of claim 13, wherein the RRM measurement configuration indicatesfrequency locations and periods of the multiple QCLed FDMed RStransmissions.
 16. The method of claim 13, further comprising:transmitting a bandwidth part (BWP) configuration to the UE indicatingan active BWP including at least one of the multiple QCLed FDMed RStransmissions; and transmitting the RRM measurement configurationindicating a measurement bandwidth for received signal strengthindicator (RSSI) measurement that is different from the active BWPconfigured to the UE.
 17. The method of claim 13, further comprising:transmitting a BWP configuration to the UE indicating an active BWPwithout the multiple QCLed FDMed RS transmissions; and transmitting theRRM measurement configuration indicating a first measurement bandwidthand a first measurement gap configuration for reference signal receivedpower (RSRP) measurement on the first measurement bandwidth thatincludes a subset of the multiple QCLed FDMed RS transmissions, and asecond measurement bandwidth and second measurement gap configurationfor RSSI measurement on the second measurement bandwidth, wherein thesecond measurement bandwidth is different from the first measurementbandwidth, and the second measurement configuration is independent fromthe first measurement configuration.
 18. The method of claim 13, furthercomprising: transmitting the RRM measurement configuration indicating: afirst measurement bandwidth for RSRP measurement including a subset ofthe multiple QCLed FDMed RS transmissions, a second measurementbandwidth for RSRQ measurement that is different from the firstmeasurement bandwidth, and time domain resources for RSSI measurementincluding a set of OFDM symbols that carries or does not carry RSs ofthe multiple QCLed FDMed RS transmissions.
 19. The method of claim 13,further comprising: transmitting a BWP configuration indicating anactive BWP to the UE; transmitting the RRM measurement configurationindicating a measurement gap configuration specifying a firstmeasurement gap and a second measurement gap at a beginning and an end,respectively, of a measurement occasion, and a repetition period of themeasurement occasion; and transmitting data during an interval betweenthe first and second measurement gaps on the active BWP.
 20. A userequipment (UE), comprising processing circuitry configured to: receive aradio resource management (RRM) measurement configuration from a basestation (BS) in a beamformed communication system, the RRM measurementconfiguration indicating presence of multiple quasi collocated (QCLed)frequency domain multiplexed (FDMed) reference signal (RS) transmissionsin a carrier, the multiple QCLed FDMed RS transmissions including afirst sequence of RS transmissions at a first frequency location and asecond sequence of RS transmissions at a second frequency location,first RSs of the first sequence of RS transmissions and second RSs ofthe second sequence of RS transmission being equivalent in terms of RRMmeasurement; and perform RRM measurement according to the received RRMmeasurement configuration using one or more of the multiple QCLed FDMedRS transmissions.
 21. The method of claim 1, wherein an RRM measurementperformed at the first frequency location using one or more first RSs isused to indicate a channel condition at the second frequency location.